Loom let-off mechanism



April 23, 1931.v VPAYNE 1,803,143

,LOOM LET-OFF MECHANISM Filed March 27, 1929 2 sheets-Sheet 1 2 JI /72 0f k L31 6550f VPg/fie x WM :lllllllllll .e'mw

April 28, 193i. v, PAYNE 1,803,143

LOOM LET -OFF MECHANISM Filed March 27. 1929 2 Sheets-Sheet 2 [/iVW/Of S 0500/ .Vffiyme 35 MW -M 730 the line 4-4 in Fig. 3;

Patented Apr. 28, 1931 UNITED STATES "PATEFT OFFIC scAR v. PAYNE, E WORCESTER, MASSACHUSETTS, 'AssIenOR 'ro' CROMPTON &

KNOWLES LOOM WORKS, o WoRcEsTER, MASSACHUSETTS, AECO PORATIQN CF34 MASSACHUSETTS LOOM LET-OFF MECHANISM Application filed. March 27,.1929. Serial No.so,4o2.

This invention relates to mechanism for tensroning the warp 1n aloom vandfor retarding'the unwinding movement of the warp beam. 7 a

' 5" It is theobject of my invention to provide an impoved construction by which the warp tension will be maintained substantially uniform, while permitting the warp to be un- Wound with great regularity; i

means for manual adjustment of the warp beam, to tighten or loosen the warp, and to provide means for sustaining the tension I weight when the warp is loosened or let back.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings in which r Fig. 1 is a side elevation of a loom embodying my improvements;

Fig. 2 is a plan view of my'improved letoff mechanism, looking in the direction of T the arrow 2 in Fig. 1;

, Fig. 3 is an end elevation of the 'let-ofl mechanism, partly in section, and taken along the line 3+3 in Fig. 2; j i

Fig. 4 is a sectional planview, taken along Fig. 5 is a detail sectional along the line 5-5 in Fig. 3; Fig. '6 is a plan viewof a ratchet member as viewed along the line 66 in Fig. 3;

plan view, taken member;

v Fig. 8 is a detail sectional view,taken along the line 8-8 in Fig. 1; and

Fig. 9 is a detail sectional elevation, taken along the line 99 in Fig. 1.

Referring to the drawings, I have shown a loom frame 10 having a warp beam B from which warp threads W pass forward to the usual lease rods 12 and harnesses 14. The loom is provided with the usual crankshaft 15 from which the lay (not shown) is oscillated.

The warpbeam B is provided with a shaftor gudgeon 20 (Fig. 4) adapted to extend loosely through an axial opening in a sup- A further objectis to provide convenient Fig. 7 is a side elevation of the ratchet 60, suspended from a segment 62 bolted to the porting member The member 21" has if hub. portion 22, the outer end of which is split, as indicated at23, and is provided with" a clamping collar 24. By adjusting the binding screw 25, the split end'ofthe hub maybe clamped tightly on the gudgeon 20, thus -fixing the supporting member 21 to the'beam B.

A member 30 is clamped on" a portion of the hub- 22 and is provided with'annular flanges 32 on which a casing 34'is rotatably mounted. A worm wheel 36 is also supported on the member 30, being preferably formed integral therewith.

A self-aligning-bearing 40 has a portion thereof fixedon the hub 22 and a second por-- tion thereof secured in a frame member 42 having av depending or bracket portion 44 (Fig. 1), vertically adjustable on the loom frame 10 and secured by bolts 45thereto.

It will be noted that the ball races in the bearing 40 are formed as segments of a circle having its center in the axis of the bearing, so that the hearing may swivel in the support 42 and adaptitself to any defect in alignment or straightness of the gudgeon "A worm (Fig. 3) is mounted on a shaft 52 rotatable in bearings 53 and 54 in the casing 34 and also having a thrust bearing 55 to resist the end thrust of the worm 50. The worm 50 engages the worm wheel 36, previously described, and causes relative angular movement between the worm wheel 36 and the casing 34. v

A weight W is mounted on a rope or cable face of a collar 66 (Figs. 6 and 7) keyed to the shaft 52 and by which the gear 64 is supported. These teeth interengage in such manner as to enable the gear 64 to turn the collar 66 and shaft 52 positively in one to engage'corresponding teeth on the upper direction, while allowing the gear 64 to slip idly relative to the collar 66 when moved in the other direction.

A hand wheel 7 0 is fixed to the upper end of the shaft 52, and a spring 72 is interposed between an upward extension of the gear 64 and the hub of the hand wheel 70, the spring acting to hold the two sets of ratchet teeth in yielding engagement. At its upper end, the gear 64 is provided with a flange 74 by which it may be grasped and raised for a purpose to be described.

A plunger 7 6 (Fig. 5) is mounted in a hori zontal bearing in the casing 34 and is provided with rack teeth 78 engaging the teeth of the. segment gear 64. The plunger 76 is also provided with a longitudinal pocket 79 in which a spring 80 is seated, the spring acting to force the plunger outward to a limit of movement establishedby a bearing plate 82.

An actuating member 84 is pivoted at- 85 on the loom frame 10 and is provided with an arm 86 connected bya link 88 to a link head 90, mounted on an eccentric 92 fixed to the crankshaft 15. As the shaft 15 ro-.

tates, the actuating member 84 is quite evidently given a short oscillating movement toward and from the plunger 76 (Fig. 5), when the latter is in engaging position.

a A cylinder or dashpot 100 (Figs. 1 and 9) is secured to the lower end of the bracket 44 and a piston 102 therein is connected by a rod 104 to a pivot 105 on the segment 62 (Fig. 1) supported by the casing 34. A bleed opening 106 is provided in the piston 102 and a cover plate 108 excludes dust and dirt from the oil or other liquid in the dashpot 100.

In order to hold the let-off Y mechanism substantially in operative position when the warp is'slackened or let back for any rea 7 son, I have provided ratchet teeth 110 (Fig.

3) on the casing 34, engaged by a pawl 112 pivoted'at 114 on the'loom frame and provided with a link and handle 116 '(Fig. 1)

extending to the front of the loom. The

pawl 112 is normally out of contact with the ratchet teeth 110, as shown in Fig. 1, but may be raised by the weaver to the position shown in Fig. 3 if he desires to let back the warp or to relieve the tension thereon for any rea son. V

Having thus described thedetails of construction of my improved let-ofi' mechanism, the operation thereof is as follows The worm 50 in effect locks theoasing 34 and segment 62 to the worm wheel 36 and thus to the wrap beam B, so that the angular clockwise movement of the warp beam as the warp is drawn off acts to raise the weight W,

which weight is selected to provide the desired warp tension.

If no provision were made for rotating the worm 50, the device would act as described until the segment 62 and weight -W reached their limit of travel, after which the loom would become inoperative.

As the casing 34 moves clockwise, however, the plunger 76 is advanced further and further into the path of movement of the actuating member 84. As the member 84 is oscillated, the plunger 76 will be moved axially thereby, rotating the worm in such a direction that the worm wheel 36 is rotated anticlockwise and the weight W is lowered.

The dotted line position of the member 84, as shown in Fig. 5, indicates that the member 84 will cause increased travel of the plunger 7 6 as the plunger advances clockwise toward alignment with the extreme lower or outer end of the member 84.. The plunger 76 is returned to the normal or outer position by its spring 80 each time the member 84 is swung away from the plunger. I

In actual operation,- the casing 34 con; tinues its clockwise movement until the plunger 7 6 has assumed such-a position that the amount by which the worm wheel 36 is rotated backward exactly corresponds to the amount by which the beam B is rotated for ward by the unwinding of the warp threads After the parts have assumed this relative position, the casing 34 and weight W remain substantially stationary, except for a slight oscillating movement caused by the beat up of the lay. The dashpot 100 is pro vided to control and reduce the oscillating movement, preventing it from building up to an undesirable extent.

It will be noted that all parts of the letofi mechanism are mounted on the bracket 44 and are vertically adjustable as a unit therewith on the loom frame 10. A

If the weaver desires to tighten or loosen); the warp independently of the automatic let-ofi',he merely raises the segment gear 64 so that the ratchet teeth thereof are out of contact with the teeth on the collar 66, thus freeing the worm 50 for manual rotation by the; hand wheel 7 0. V

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, otherwise than: as set forth inthe claims, but what. I claim is p 1. In a 100111, a warp beam, a worinwheel fixed thereto, a 1 weighted casing pivotally mounted concentric with said worm wheel, a

worm rotatably mounted in said casing and:

2. In a loom, a warp beam, a worm Wheel fixed thereto, a weighted casing pivotally mounted concentric with said worm wheel, a

worm rotatably mounted in said casing and engaging said worm wheel, means to rotate said worm, actuating means movable in afixed path in timed relation to the movement of the lay and positioned for intermittent engagement with said worm rotating means, thereby causing rotation of said worm, the extent of movement of said worm rotating means being controlled by'the angular position of said casing about its axis and relative to said actuating means, and manually operated means for preventing rearward rotation of said warp beam.

3. In a loom, a warp beam, a worm wheel fixed thereto, a weighted casing pivotally mounted concentric with said'worm wheel, a worm rotatably mounted in said casing and engaging said worm wheel, and means to intermittently actuate said worm as the warp is unwound from said beam, said casing being relatively movable angularly in one direction by the unwinding movement of the warp beam, and said casing receiving a'compensating relative angular movement in the oppo site direction by the co-action of said worm and worm wheel and a releasable clutch con nection being provided between said worm and said actuating means whereby said Worm may be released for manual actuation. V

4. The combination in a loom as set forth in claim 3, in which a gear is mounted co-axial with said worm, a clutch connection is provided between said gear and said worm, and a rack engages said gear, said rack being movable longitudinally in one direction by said actuating means to rotate said worm and gear.

5. The combination in a loom as set forth in claim 3, in which a gear is mounted co-axial with said worm, a clutch connection is provided between said gear and said worm, and a rack engages said gear, said rack being movable longitudinally in one direction by said actuating means to rotate said gear and worm and being movable in the opposite direction by a spring.

6. In a loom, a warp beam having a gudgeon, a supporting member having an open ing to receive said gudgeon, means to clamp said gudgeon in said member, a self-aligning bearing for said member, a worm wheel mounted on said member, a casing pivoted about the axis of said member, a worm mounted in said casing and engaging said worm wheel, and automatic means to turn said Worm to compensate for the angular advance movement of said casing caused by the unwinding of the warp from said beam.

In testimony whereof I have hereunto affixed my signature.

- OSCAR V. PAYNE. 

